nptl: Remove always-disabled debugging support

This removes the DEBUGGING_P macro and the __pthread_debug variable.
The __find_in_stack_list function is now unused and deleted as well.

Reviewed-by: Adhemerval Zanella  <adhemerval.zanella@linaro.org>

nptl/pthreadP.h

@@ -243,23 +243,11 @@ libc_hidden_proto (__pthread_tpp_change_priority)
 extern int __pthread_current_priority (void);
 libc_hidden_proto (__pthread_current_priority)
 
-/* The library can run in debugging mode where it performs a lot more
+/* This will not catch all invalid descriptors but is better than
-   tests.  */
+   nothing.  And if the test triggers the thread descriptor is
-extern int __pthread_debug attribute_hidden;
+   guaranteed to be invalid.  */
-/** For now disable debugging support.  */
+#define INVALID_TD_P(pd) __builtin_expect ((pd)->tid <= 0, 0)
-#if 0
+#define INVALID_NOT_TERMINATED_TD_P(pd) __builtin_expect ((pd)->tid < 0, 0)
-# define DEBUGGING_P __builtin_expect (__pthread_debug, 0)
-# define INVALID_TD_P(pd) (DEBUGGING_P && __find_in_stack_list (pd) == NULL)
-# define INVALID_NOT_TERMINATED_TD_P(pd) INVALID_TD_P (pd)
-#else
-# define DEBUGGING_P 0
-/* Simplified test.  This will not catch all invalid descriptors but
-   is better than nothing.  And if the test triggers the thread
-   descriptor is guaranteed to be invalid.  */
-# define INVALID_TD_P(pd) __builtin_expect ((pd)->tid <= 0, 0)
-# define INVALID_NOT_TERMINATED_TD_P(pd) __builtin_expect ((pd)->tid < 0, 0)
-#endif
-
 
 /* Cancellation test.  */
 #define CANCELLATION_P(self) \
@@ -322,10 +310,6 @@ __do_cancel (void)
 
 /* Internal prototypes.  */
 
-/* Thread list handling.  */
-extern struct pthread *__find_in_stack_list (struct pthread *pd)
-     attribute_hidden;
-
 /* Deallocate a thread's stack after optionally making sure the thread
    descriptor is still valid.  */
 extern void __free_tcb (struct pthread *pd) attribute_hidden;

nptl/pthread_create.c

@@ -42,9 +42,6 @@
 #include <stap-probe.h>
 
 
-/* Nozero if debugging mode is enabled.  */
-int __pthread_debug;
-
 /* Globally enabled events.  */
 static td_thr_events_t __nptl_threads_events __attribute_used__;
 
@@ -210,46 +207,6 @@ static int create_thread (struct pthread *pd, const struct pthread_attr *attr,
 
 #include <createthread.c>
 
-
-struct pthread *
-__find_in_stack_list (struct pthread *pd)
-{
-  list_t *entry;
-  struct pthread *result = NULL;
-
-  lll_lock (GL (dl_stack_cache_lock), LLL_PRIVATE);
-
-  list_for_each (entry, &GL (dl_stack_used))
-    {
-      struct pthread *curp;
-
-      curp = list_entry (entry, struct pthread, list);
-      if (curp == pd)
-	{
-	  result = curp;
-	  break;
-	}
-    }
-
-  if (result == NULL)
-    list_for_each (entry, &GL (dl_stack_user))
-      {
-	struct pthread *curp;
-
-	curp = list_entry (entry, struct pthread, list);
-	if (curp == pd)
-	  {
-	    result = curp;
-	    break;
-	  }
-      }
-
-  lll_unlock (GL (dl_stack_cache_lock), LLL_PRIVATE);
-
-  return result;
-}
-
-
 /* Deallocate a thread's stack after optionally making sure the thread
    descriptor is still valid.  */
 void
@@ -259,12 +216,6 @@ __free_tcb (struct pthread *pd)
   if (__builtin_expect (atomic_bit_test_set (&pd->cancelhandling,
 					     TERMINATED_BIT) == 0, 1))
     {
-      /* Remove the descriptor from the list.  */
-      if (DEBUGGING_P && __find_in_stack_list (pd) == NULL)
-	/* Something is really wrong.  The descriptor for a still
-	   running thread is gone.  */
-	abort ();
-
       /* Free TPP data.  */
       if (__glibc_unlikely (pd->tpp != NULL))
 	{

nptl/pthread_sigqueue.c

@@ -31,11 +31,6 @@ pthread_sigqueue (pthread_t threadid, int signo, const union sigval value)
 #ifdef __NR_rt_tgsigqueueinfo
   struct pthread *pd = (struct pthread *) threadid;
 
-  /* Make sure the descriptor is valid.  */
-  if (DEBUGGING_P && INVALID_TD_P (pd))
-    /* Not a valid thread handle.  */
-    return ESRCH;
-
   /* Force load of pd->tid into local variable or register.  Otherwise
      if a thread exits between ESRCH test and tgkill, we might return
      EINVAL, because pd->tid would be cleared by the kernel.  */